This research aims to overview the English-medium instruction (EMI) situation in Korean Higher education (HE), briefly describing and studying HE policies and examining their impact on Korean teachers and students. The case of the Korea Advanced Institute of Science and Technology (KAIST) has been addressed and investigated intensively in the Korean context concerning STEM. It is significant to examine the 21st-century controversial issues regarding English Medium Instruction (EMI) implementation in Korean HE, focusing on a case study of the 'KAIST'. Notably, the issue of EMI has been questioned across Korean society and educational fields. This research focuses on reviewing relevant literature and analysing it in detail to learn how KAIST helps us understand Koreans' EMI pedagogy methods and education-related (Korea's EMI policy implementation in general and EMI's impact on students and teachers) issues. However, the secondary materials are based on press reports, public statements of the people concerned, and statistical data. It lays the groundwork for a step deeper future qualitative or quantitative approaches to the case of KAIST for the improvement and success of EMI in Korean HE. It has been found that modern EMI pedagogy methods can lower excessive pressure so that students and teachers can educate and enjoy the EMI education policy.